Conditional HttpCache for Drupal

gistfile1.php

<?php

use Drupal\Core\DrupalKernel;
use Symfony\Component\HttpFoundation\Request;
use Symfony\Component\HttpKernel\HttpCache\Esi;
use Symfony\Component\HttpKernel\HttpCache\HttpCache;
use Symfony\Component\HttpKernel\HttpCache\Store;

// Build a drupal kernel
$kernel = new DrupalKernel()

$request = Request::createFromGlobals()

$esi = new Esi()
if (!$esi->hasSurrogateEsiCapability($request)) {
    // There is no reverse proxy supporting ESI in front, so add the Symfony HttpCache
    // this is not executed when you have Varnish in front and properly configured
    $kernel = new HttpCache($kernel, new Store(), $esi);
}

$response = $kernel->handle($request);